Toilet flush



Nov. 19, 1935. L. w. STEVENS TOILET FLUSH Filed June 15, 1954 PatentedNov. 19, 1935 UNITED STATES PATENT OFFICE TOILET FLUSH Llewellyn W.Stevens, Needham, Mass.

Application June 15, 1934, Serial No. 730,760 7 17 Claims.

The present invention relates to fiush tanks and valves, for toiletsparticularly, but applicable to other more or less analogous uses wherea rapid and copious flow of water may be required for a brief length oftime, while long periods may elapse during which the water should beprevented from flowing. Inasmuch as the toilet flushing use is the onewhich I have had particularly in mind in developing the form of theinvention herein shown and described, I will in the followingspecification explain the purpose and utility of the invention withreference to that use; but without intending thereby to imply anyunnecessary limitation in the scope of the invention or the protectionwhich I claim for it.

Essential or important features of flush valves are that they be capableof delivering a large enough volume of water, suddenly enough, to flushthe toilet completely, with economy in expenditure of water, that thevalve be leakage tight and remain so without attention and repair overthe longest possible period of time, that it be operable manually torelease the flushing charge of water with a minimum of muscular effort,and that it be efiicient after even long periods of disuse. The flushingattachments of the character to which I have reference, heretofore used,consist of a tank to hold the water, a float controlled inlet valve tomaintain the water supply in the tank automatically at a given level,and an outlet valve which is opened by an external handle and is heldopen by a float device or trip mechanism until the desired amount ofwater has been discharged. The valves heretofore used are notpermanently leakage tight, but begin to leak after short periods of use,with wastage of the water and failure to maintain a sufficient quantityin the tank to perform the flushing operation satisfactorily at need.They also include metal parts which are subject to corrosion by chemicalaction of the water and to injury otherwise by abrasion. The main objectof this invention is to provide a valve or valve substitute which issealed by the water contained in the tank, hence is leakage-proof, andmay be made of noncorrodible materials, while possessing all theessential and desirable qualities of a flush valve. Although the valvesubstitute of this invention differs from the common types of valve inhaving no contacting valve body and seat, yet for convenience ofdescription I will generally refer to it as a valve hereafter in thisspecification. Other objects are to provide a novel and improved tripdevice for holding the valve open until the predetermined quantity ofwater has been discharged, which is not liable to get out of order; andto provide other improvements which are set forth in the followingspecification.

In the drawing,--

Fig. 1 is a horizontal section of a flush tank '5 showing in plan viewthe elements of my novel flush valve and accessories in place therein;

Fig. 2 is a vertical section of the flush valve and its accessoriesshown in open position, and showing also both in section and inelevation fragments of the tank in which it is installed;

Fig. 3 is a sectional view similar to Fig. 2, showing the valve inclosed or sealing position;

Fig. 4 is a cross section of the valve takenon line 4-5 of Fig. 3;

Fig. 5 is an elevation of the Valve holding trip device as seen from theleft hand side of Figs. 1 and 3.

Like reference characters designate the same parts wherever they occurin all the figures.

The principle'on which my novel flush valve operates is that of theU-tube type of manometer; the equivalent of a U-tube, or a series ofU-tubes in tandem, in which the water supply for flushing purposes isthe sealing medium confining a body, or a series of bodies, of air,between the tank outlet and the head of water in the tank. Such U-tubeequivalent is constructed of separable parts, one of which is removedfrom or uncovered by the water every time the tank is discharged, whilethe other remains submerged in the water, whereby the bodies of air andwater necessary to maintain the seal when the valve is closed, areconstantlyrenewed. Inasmuch as the practical limitations of space forinstallation preclude making the U-tube element of as great height asthe depth of water maintained in the tank, it is practically necessaryto provide the valve with the equivalent of two or more U-tubes inseries. The embodiment here illustrated has been designed for aconventional design of flush tank adapted to contain water to a depth ofabout ten inches, and in which the operating mechanism is capable oflifting the valve between two and three inches.

The design of flush valve here illustrated comprises two main members,one of which is normally stationary, being secured to the bottom of thetank, and the other is liftable. The stationary member is composed of aseries of coaxial ornested, preferably cylindrical, walls or rings 6, 1,8, 9 and I0, rising vertically from a base H which is secured by anysuitable means to the tank bottom preferably in central alinement withthe discharge tube I2 which leads from the 55 with such tube.

- stantial height or depth, proportioned to the available lift of themovable member. In combination with the base ll they form in effect aseries of nested cups with spaces between their respective walls. Theinnermost cup has no bottom, for the base contains a central hole inregister with the outlet tube I2, wherefore the ring 6 forms an upwardcontinuation of the discharge passage.

The movable member consists of similar walls or rings i3, it, l5, l6 andI1 connected to a base l8 so as to constitute in effect a nested seriesof coaxial inverted cups, of which the base I8 forms the inverted bottomcommon to all. The inverted cup series are widths or diametersintermediate those of the upright series, except that the outermost wallI1 is larger than the wall It. A concentric tube E9 of smaller diameterthan the ring or wall 6 passes through the base l8 in leakage-tightconnection therewith and rises to a height enabling it to serve as anoverflow if the tank is filled above the prescribed limit. It serves thefunction of a closure for the innermost inverted cup so long as thewater level in the tank is within such limit.

The upper edges of the rings 1-!!! inclusive preferably lie in the samehorizontal plane; and the lower edges of the rings l3-il inclusive arealso preferably in a single horizontal plane. The location of the latterplane, however, may be shifted by raising and lowering of the movablemember to a position in which the movable member is entirely above thefixed member, as shown in Fig. 2, and a position in which two sets ofrings are interleaved with the lower edges of the movable set, near butseparated from, the base of the fixed member, and the upper edges of thestationary rings near, but separated from, the base N3 of the movablemember. The raised position of the movable member should be high enoughto make the circumferential area between the adjacent rims of the ring 6and tube i9 as great as the transverse area within the ring 6, in orderto permit as rapid an outflow of water as the tube 5 can accommodate.While the movable member remains in raised position, water is dischargedfrom the tank; and when the tank water level has descended below thelower edges of the inverted cups, any water which may have entered thesecups flows out and is replaced by air. The lowest level to which thewater supply may descend is that of the plane in which the upper edgesof the rings 6-H] lie, The spaces surrounded by these rings, except thatof the innermost one, are then filled with water.

The valve is closed by descent of the movable member to substantiallythe position shown in Fig. 3, whereupon the interleaved rings of the twomembers form in effect a series of U-tubes in tandem connection. Thewater legs of these U-tubes are designated w, 112 w and W in Fig. 3, andthe air spaces by a, a a and 0. There is also a space 20 between theouter rings 10 and ll in which water enters from the body of the tank asthe level rises in the latter, compressing the air originally in thatspace and thereby causing a distribution of air pressure and waterthroughout the other spaces between the interleaved rings. Thus an airpressure exists in the space 0; equal to the head of water in the leg w;in the space 0. equal to the sum of the water heads to and m and so on,until the pressure in the outermost air space becomes equal to the sumof the water columns in all of the Water legs. In the foregoingdescription, the term water column is intended to mean the height ofwater in any water leg above the water level in the next outer air spaceor leg.

The valve is capable of sealing in the tank a head of water equal to theair pressure in the air space (1 With a perfect distribution of air andwater, the maximum head thus maintainable would be approximately equalto the number of water columns multiplied by the height of overlap ofthe two sets of rings. It is found in practice, however, the watercolumns as above defined are not always and in all instances as high assuch overlapping height, wherefore in order to maintain a given heightof water in the tank, with a given limit of lift of the valve,

the number of overlapping rings is made greater than the theoreticallysufficient number.

The movable and stationary members of the valves are so designed as todiameters and thickness of their rings, that the two groups of ringswill intermesh readily and with sufficient clearance to precludecapillary and siphonic action. The spaces between the contiguousinterleaved rings must be at least wide enough to permit free flow ofair and water past one another in achieving the distribution which iseffected by the rising water head as the tank fills. Oneeighth of aninch is a sufficient, although not the minimum operative, width of suchspaces;

But the spaces may be made of any greater width, limited only by thedimensions of the tank itself.

The upper member is guided in its movements, and centered with respectto the lower member, by vertical tubes 23 on the outside of the outerring I1 of the upper member, and rods 2| rising from the base i! of thelower member into these tubes and having a free sliding fit therein.Preferably there are three such guide tubes and rods spaced equallyaround the circumference of the valve, but their number and distributionmay be varied. The rods are of course long enough to project into thetubes when the upper member is fully raised, and the tubes are longenough to enclose the rods when this member is fully lowered, and areclosed. at the top except for a vent of such dimensions as to cause thetube and rod to coact in the manner of a hydraulic check in cushioningdescent of the movable member. While other types or forms of guide maybe used satisfactorily, that just described has advantages over othersfor construction purposes.

The upper valve member is raised by lifting mechanism. One of manydevices which may be used for the purpose is shown herein, con sistingof a handle 22 on the outer end of a shaft 23 which passes through a.bushing 24 secured in the front wall 25 of the tank. An arm 25 on thisshaft is connected by a link 2'! with the short arm of a lever 28pivoted at 29 to a bracket 3!] secured to the bushing. The long arm ofthis lever swings in a vertical plane beside the overflow tube l9 andcarries a wiper 3| beneath a roll 32 pinned to the adjacent side of thetube. Turning of the handle raises the wiper from its lowered position,shown by full lines in Fig. 2, to a raised position approximating thatshown by dotted lines in the same figure, thereby lifting the uppervalve member.

Said valve member is held in its raised position while the tankdischarges, and is then released and allowed to descend, by a tripdevice containing novel features for which I claim protection. A latchabutment 33 is connected to one side of the movablemember andconstructed to present a square abutting surface 34 at its lower end,and an inclined surface at its outer side. A latch or trip lever 35 ispivoted at 36 to the base of the fixed valve member and carries acomplemental abutment 31 adapted to underlie and arrest the abutmentshoulder 34 when the movable valve member is raised. Preferably thiscomplemental abutment is made as a roll suitably journaled to the lever35 at a height adapting it to support the movable member at the heightprescribed for permitting free discharge of the Water.

shown in broken lines.

The trip lever carries a combined water weight and float 38 which isactuated by gravity and the water in the tank to put the trip lever inlooking and releasing positions. The combined float and weight device isa closed box or can,

" light in weight and having thin walls, which is entirely closed, waterand air tight, except for one or more holes 39 in its sides and a smalldrainage opening 40 in its bottom. The holes 39 are large enough topermit passage of air and water in either direction, and are at pointslow enough with respect to the top of the boxto entrap enough air toserve as a float when submerged, and to retain enough water to act as aweight, withdrawing the abutment roll 3! from the abutment latch, whenthe water in the tank subsides to its low level. As this weight islocated entirely at one side of the vertical through the pivot 38, itbecomes effective to withdraw the lever, overcoming the resistance tosuch withdrawal caused by the weight of the upper valve member, when thewater has subsided to approximately the level shown in Fig. 2. It isthere shown by full lines as about to release the upper valve memberafter having withdrawn from the locking position The height of thebottom of the box, and of the holes 39 with respect to its bottom andtop, are established by calculation and design so as to give thenecessary buoyancy for automatic latching when the tank is full, and tohold the upper valve member elevated until after the water level hasfallen low enough to permit water to drain out of the inverted nest ofcups. The openings 39 permit the quantities of air and water in thefloat-weight device to be renewed and reestablished with each use of theis emptied and left out of service. It is so small that the leakage lossthrough it during operation is negligible.

A considerable weight is needed to sink the air filled upper member intothe water filled lower member. To furnish such a weight, without at thesame time so loading the upper member as to make it difiicult to beraised by the lifting mechanism, was a problem which I have solved byproviding a water weight 4| on top of the upper valve member. The waterfurnishing this weight is held in an open cup 42 of suitable width anddepth, which is refilled with each filling of the tank. Its content ofwater adds nothing to the weight of the valve when lifted for flushing,

being balanced by the water in the tank; but after the tank water hasrun out, its fullaweight becomes available to lower the valve member.There is a small drainage hole 43 in the side of cup 42 near the bottom,for the same purpose as the drainage hole 40, the capacity of which isso small that no appreciable reduction of the effective weight occursduring operation. 7 v

The upper valve member descends until arrested by a stop 44, which ishere shown as a part of the trip lever 35 beneath the latch member 33.In its descent, the excess quantities of air and water trapped in thenested cups escape by the pathsof least resistance, leaving enough airand water to be afterwards distributed by the rising head in the tank toform manometer 001- umns of the nature previously described. As thequantities of water and air necessary for this purpose are automaticallyrenewed, in excess, with each flushing use, the valveremains'serviceable and incapable of leaking. 1 5 A feature of thisvalve of great practical value is that all of its parts may be moldedfrom bakelite or some other suitable plastic which is impervious tocorrosive action by water. This statement applies to both elements ofthe valve, as well as to all other parts of the entire assemblage.

What I claim and desire to secure by Letters Patent is:

1. An outlet valve for liquid containers comprising a plurality ofupright stationary cups in nested arrangement having a central outlet,and a plurality of inverted cups in nested arrangements, the walls ofwhich are respectively positionedand dimensioned to pass into and. outof interleaved relationship with the walls of the first series of cupsby up and down movement, and the walls of both sets of cups being spacedapart from one another widely enough when in such interleavedarrangement to avoid capillary action. 4 2. A discharge valve comprisinga stationary member having an outlet and a movable member adapted to beraised and lowered with respect to said stationary member; said twomembers having cooperating means adapted to form a series of U-tubedmanometers in tandem between said outlet and the liquid space of acontainer in which the discharge valve may be placed, whereby the liquidcontent of the container when entrapped between said members may form aliquid seal ef- 45 fective to sustain a head of the same liquid in thecontainer greater than the height and lift of the movable member, andprovisions for raising said movable member to a height clear of thestationary member. 3. The combination with a tank adapted to containliquid and having an outlet, of a stationary valve member having anopening in register with said outlet, and a movable valve member adaptedto be raised'clear of the stationary memher and to be lowered intocomplemental relationship therewith so as to form in effect a, series ofU-tube manometers in tandem between the outlet and the liquid containingspace of the tank.

4. The combination with a tank having an out- 0 let, of a number greaterthan two, of substantially coaxial rings having substantial height, thespace surrounded by the innermost ring being in communication with saidoutlet, and the annular 7 spaces between the rings being closed at thebotraising the second series of rings to a height clear of the firstnamed group of rings.

5. A flush apparatus comprising a tank having an outlet, a group of morethan two nested upright cups having an opening through the bottom of theinnermost cup in register with said outlet, a set of more than twonested inverted cups, the walls of which are spaced and dimensioned soas to be placeab-le in and out of interleaved relationship with thewalls of the upright cups, with spaces between adjacent walls wideenough for pressure-equalizing opposite flow of water and air, andguiding means for the inverted cups arranged to effect such interleavedrelationship when the inverted cups are lowered, while permitting themto be raised to a height such that liquid may flow from the tank to theoutlet between the rims of the upright and inverted cups.

6. A flush apparatus comprising a tank having an outlet, a group of morethan two nested upright cups having an opening through the bottom of theinnermost cup in register with said outlet, a set of more than twonested, inverted cups, the walls of which are spaced and dimensioned soas to be placeable in and out of interleaved relationship with the wallsof the upright cups with room between adjacent walls for interchange ofair and water, means for raising the inverted cups to a position wheretheir lower rims are above the top rims of the upright cups, a detentfor holding the inverted cups in such raised position, and meanscontrolled by the liquid in the tank for releasing said detent after thelevel of liquid in the tank has subsided below the rims of the invertedcups.

7. A flush apparatus comprising a tank having an outlet, a group ofnested upright cups having an opening through the bottom of theinnermost cup in register with said outlet, a set of nested invertedcups, the walls of which are spaced and dimensioned so as to beplaceable in and out of interleaved relationship with the walls of theupright cups, the number of cups and the spacing of their walls beingsuflicient to entrap water and air and permit flow of water and air intoalternate spaces between the interleaved walls to form a plurality ofU-tube manometers in tandem, effective to sustain a head of water in thetank greater than the height and lift of the lnverted cups, a detenthaving a float element which is buoyant in the liquid contents of thefilled tank and thereby made potentially operative for arresting theraised inverted cups, the latter having a latch element engageable withsaid detent when in raised position clear of the upright cups, thedetent being gravity operated to release said latch element when theliquid in the tank subsides to a level below the rims of the raisedinverted cups.

8. In a flush tank and valve combination, a stationary valve element, aliftable valve element adapted to prevent discharge of water from thetank when lowered, and to permit such discharge when raised, having alatching abutment, a detent cooperative with said abutment to hold saidmovable valve element in raised position, and a combined float andweight associated with said detent located to be submerged when the tankis full, said float having an air-containing upper space, the buoyancyof which when submerged makes the detent potentially operative tointerlock with said abutment upon raising of the movable valve element,and a water-containing lower portion which is out of water when the tankis discharged and the weight of which is then sufiicient to causerelease of the detent.

9. In a flush tank having an outlet, a liftable valve element foropening and closing said out let, a detent pivotally mounted at a lowpoint and having an abutment at a height above its pivot adapted to passunder a complemental abutment on said valve element when the latter israised, an air entrapping float and a water container connected to saiddetent in a position to be sub- 10 merged and uncovered by rise anddescent of water in the tank, and to exert force tending to place thedetent abutment under the latch abutment of the valve element whensubmerged, and to displace said abutment when uncovered by subsidingwater.

10. In a flush tank having an outlet, a liitable valve element foropening and closing said outlet, a detent pivotally mounted at a lowpoint and having an abutment at a height above its pivot adapted to passunder a complemental abutment on said valve element when the latter israised, an air entrapping float and a water container connected to saiddetent in a position to be submerged and uncovered by rise and descentof water in the tank, and to exert force tending to place the detentabutment under the latch abutment of the valve element when submerged,and to displace said abutment when uncovered by subsiding water, saidfloat and container being open for entrance of air and water when,respectively, uncovered by, and submerged in, the water in the tank.

11. In a flush tank having an outlet, a liftable valve element foropening and closing said outlet, having a latching abutment, a detentpivotally mounted in position to interlock with said abutment when thevalve element is raised, a hollow receptacle closed at top and bottomand having an opening at an intermediate height in its side adapted topermit inward and outward flow of air and water, connected to saiddetent in a position such that it is submerged in water when the tank isfull and above water when the tank is empty, and at one side of avertical line through the pivot of the detent.

12. The combination with a tank having an outlet, of an outlet valvecomprising a coaxial series of upright cups in communication with saidoutlet through the innermost cup, and otherwise closed at the bottom, aninverted series of cups closed at the top and arranged to be interleavedwith the upright cups, and to be withdrawn therefrom, guiding means forcentering said inverted cups with respect to the upright cups andguiding the movement of the inverted cups, said guiding means comprisingrods rising from the upright cups and tubes carried by the inverted cupsin which said rods are slidingly fitted, said rods and tubes beingspaced apart around the circumference of the cups.

13. The combination with a tank having an outlet, of an outlet valvecomprising a coaxial series of upright cups in communication with saidoutlet through the innermost cup, and otherwise closed at the bottom, aninverted series of cups closed at the top and arranged to be interleavedwith the upright cups, and to be withdrawn therefrom, guiding means forcentering said inverted cups with respect to the upright cups andguiding the movement of the inverted cups, said means comprising rodsrising from the upright cups and tubes carried by the inverted cups inwhich said rods are slidingly fitted, said tubes being closed at theirupper ends and having (I vent openings whereby they act as hydraulicchecks to retard descent of the inverted cups from a raised position.

14. The combination with a tank having an outlet, of an outlet valvecomprising a coaxial series of upright cups in communication with saidoutlet through the innermost cup, and otherwise closed at the bottom, aninverted series of cups closed at the top and arranged to be interleavedwith the upright cups, and to be withdrawn therefrom, means for liftingthe inverted cup assemblage to a position entirely withdrawn from theupright cup assemblage, and a water weight connected to said invertedcup assemblage in position to be submerged when the tank is full and tobe above the level to which the water subsides by discharge through theoutlet.

15. The combination with a tank having an outlet, of an outlet valvecomprising a coaxial series of upright cups in communication with saidoutlet through the innermost cup, and otherwise closed at the bottom, aninverted series of cups closed at the top and arranged to be interleavedwith the upright cups, and to be withdrawn therefrom, a water containercarried by the inverted cup series in position to be suband to displaceentrapped water and air therein, when the water content of the tank isdischarged. 16. A toilet flush comprising a tank having an outlet, avalve comprising a two part U-tube manometer having a plurality of airand water 5 legs in series, one of the parts of which is stationary inconnection with the outlet, and the other of which is shiftable from aposition in relation with the fixed part wherein it creates a seal byentrapment of water to prevent flow of the tank water through theoutlet, to a raised position where it permits such outflow and is abovethe level to which the water in the tank then subsides, whereby itsinterior spaces are cleared of water and filled with air. 1'7. In atoilet flush tank having an outlet, a manometer outlet valve comprisinga fixed element in connection with the outlet and a liftable elementinterleaved with the fixed element to provide a number of alternate airand water legs in tandem arrangement suificient to balance a head ofwater in the tank greater than the height and lift of said liftableelement, and means for separating the movable member from the fixedmember for flushing, to a position where the fixed section is open to befilled with water and the movable section is clear of the water when thetank is empty and whereby the supply of air in its air spaces isrenewed.

LLEWELLYN W. STEVENS.

